Remove permitting of 8 byte nonce with PolyChaCha
Also unify nonce length checking
Signed-off-by: Paul Elliott <paul.elliott@arm.com>
diff --git a/library/psa_crypto_aead.c b/library/psa_crypto_aead.c
index 3b8fdc8..1a515a1 100644
--- a/library/psa_crypto_aead.c
+++ b/library/psa_crypto_aead.c
@@ -247,6 +247,21 @@
return( PSA_SUCCESS );
}
+static psa_status_t mbedtls_aead_check_nonce_length(
+ mbedtls_psa_aead_operation_t *operation,
+ size_t nonce_length )
+{
+#if defined(MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305)
+ if( operation->alg == PSA_ALG_CHACHA20_POLY1305 )
+ {
+ if( nonce_length != 12 )
+ return( PSA_ERROR_NOT_SUPPORTED );
+ }
+#endif /* MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305 */
+
+ return PSA_SUCCESS;
+}
+
psa_status_t mbedtls_psa_aead_decrypt(
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer, size_t key_buffer_size,
@@ -272,6 +287,13 @@
if( status != PSA_SUCCESS )
goto exit;
+ if( mbedtls_aead_check_nonce_length( &operation, nonce_length )
+ != PSA_SUCCESS)
+ {
+ status = PSA_ERROR_NOT_SUPPORTED;
+ goto exit;
+ }
+
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CCM)
if( operation.alg == PSA_ALG_CCM )
{
@@ -303,7 +325,7 @@
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305)
if( operation.alg == PSA_ALG_CHACHA20_POLY1305 )
{
- if( nonce_length != 12 || operation.tag_length != 16 )
+ if( operation.tag_length != 16 )
{
status = PSA_ERROR_NOT_SUPPORTED;
goto exit;
@@ -397,6 +419,12 @@
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
+ if( mbedtls_aead_check_nonce_length( operation, nonce_length )
+ != PSA_SUCCESS)
+ {
+ return( PSA_ERROR_INVALID_ARGUMENT );
+ }
+
#if defined(MBEDTLS_PSA_BUILTIN_ALG_GCM)
if( operation->alg == PSA_ALG_GCM )
{
@@ -412,11 +440,6 @@
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305)
if( operation->alg == PSA_ALG_CHACHA20_POLY1305 )
{
- if( nonce_length != 12 && nonce_length != 8)
- {
- return( PSA_ERROR_INVALID_ARGUMENT );
- }
-
status = mbedtls_to_psa_error(
mbedtls_chachapoly_starts( &operation->ctx.chachapoly,
nonce,